﻿// ———————————————————————–
// <copyright file="LocationExternalPolygon.cs" company="The MITRE Corporation">
//    Copyright (c) 2014 The MITRE Corporation. All rights reserved.
//    Licensed under the Apache License, Version 2.0 (the "License");
//    you may not use this file except in compliance with the License.
//    You may obtain a copy of the License at
//    http://www.apache.org/licenses/LICENSE-2.0
//    Unless required by applicable law or agreed to in writing, software
//    distributed under the License is distributed on an "AS IS" BASIS,
//    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
//    See the License for the specific language governing permissions and
//    limitations under the License.
// </copyright>
// ———————————————————————–
/////////////////////////////////////////////////////////////////////////////////////////////////
// LocationExternalPolygon.cs:
//
// An area region described by a polygon with no interior region, using WGS84 coordinates.
//
// Project: IC.NET - CAD Library
// Author:  Jim Cronin - MITRE
/////////////////////////////////////////////////////////////////////////////////////////////////

// Copyright (c) 2014 The MITRE Corporation. All rights reserved.
//
// NOTICE
// This software was produced for the U. S. Government
// under Contract No. FA8721-09-C-0001, and is
// subject to the Rights in Noncommercial Computer Software
// and Noncommercial Computer Software Documentation Clause
// (DFARS) 252.227-7014 (JUN 1995)

using System;
using System.Xml;
using EDXLSharp.NIEMCore;
using GeoOASISWhereLib;

namespace EDXLSharp.NIEMMilOpsLib
{
  /// <summary>
  /// An area region described by a polygon with no interior region, using WGS84 coordinates.
  /// </summary>
  public class LocationExternalPolygon : IAreaRegion
  {
    //TODO: LocationExternalPolygon - Not using ComplexTypeBase at this time - expand later if needed

    public GMLPolygon Polygon;

    /// <summary>
    /// Writes this Object to an inline XML Document
    /// </summary>
    /// <param name="xwriter">Valid XMLWriter</param>
    /// <exception cref="System.ArgumentNullException">Thrown if xwriter is null</exception>
    /// <exception cref="EDXLSharp.ValidationException">Thrown if the object fails to validate</exception>
    public void WriteXML(XmlWriter xwriter)
    {
      if (xwriter == null)
      {
        throw new ArgumentNullException("xwriter");
      }

      Validate();

      xwriter.WriteStartElement("LocationExternalPolygon", EDXLConstants.MilopsNamespace);
      Polygon.WriteXML(xwriter);
      xwriter.WriteEndElement();
    }

    /// <summary>
    /// Reads this Object's values from an XML nodelist
    /// </summary>
    /// <param name="rootnode">root XML Node of the Object element</param>
    /// <exception cref="System.ArgumentNullException">Thrown if rootnode is null</exception>
    /// <exception cref="System.ArgumentException">Thrown if the rootnode is not the correct type</exception>
    /// <exception cref="EDXLSharp.ValidationException">Thrown if the object fails to validate</exception>
    public void ReadXML(XmlNode rootnode)
    {
      if (rootnode == null)
      {
        throw new ArgumentNullException("rootnode");
      }
      if (rootnode.LocalName != "LocationExternalPolygon")
      {
        throw new ArgumentException("Unexpected element " + rootnode.LocalName + " instead of LocationExternalPolygon");
      }

      if (rootnode.ChildNodes.Count != 1)
      {
        throw new ValidationException("LocationExternalPolygon should have exactly one child");
      }

      try
      {
        Polygon = new GMLPolygon();
        Polygon.ReadXML(rootnode.ChildNodes[0]);
      }
      catch (Exception ex)
      {
        throw new ValidationException("Failed to parse Polygon from XML. See inner exception for more details", ex);
      }

      this.Validate();
    }

    /// <summary>
    /// Validates This Message element For Required Values and Conformance
    /// </summary>
    /// <exception cref="EDXLSharp.ValidationException">Thrown if the object fails to validate</exception>
    public void Validate()
    {
      //TODO: LocationExternalPolygon.Validate - verify that this validation is correct

      //Elements of mof:ExternalPolygonType MUST use gml:exterior and gml:LinearRing.
      if (Polygon.Exterior == null) //Polygon.Exterior is of type GMLLinearRing
      {
        throw new ValidationException("LocationPolygonExternal MUST use gml:Exterior and gml:LinearRing");
      }

      //Elements of mof:ExternalPolygonType MUST NOT use gml:interior.
      if (Polygon.Interior != null && Polygon.Interior.Count > 0)
      {
        throw new ValidationException("LocationPolygonExternal MUST NOT use gml:interior");
      }

      //Elements of mof:ExternalPolygonType MUST use gml:pos.
      if (Polygon.Exterior.PosList == null || Polygon.Exterior.PosList.PosList == null || Polygon.Exterior.PosList.PosList.Count == 0)
      {
        throw new ValidationException("LocationPolygonExternal MUST use gml:pos");
      }

      //Elements of mof:ExternalPolygonType MUST use the WGS84 coordinate reference system. 
      Uri wgsUri = new Uri("http://metadata.ces.mil/mdr/ns/GSIP/crs/WGS84E_3D");
      if ((Polygon.SrsName.Equals(wgsUri) || Polygon.Exterior.SrsName.Equals(wgsUri) || Polygon.Exterior.PosList.SrsName.Equals(wgsUri)) == false)
      {
        throw new ValidationException("LocationPolygonExternal MUST use the WGS84 coordinate reference system (http://metadata.ces.mil/mdr/ns/GSIP/crs/WGS84E_3D)");
      }
    }

    /// <summary>
    /// Parses a LocationExternalPolygon from an XML node
    /// </summary>
    /// <param name="node">The XML to parse</param>
    /// <returns>A new instance of LocationExternalPolygon from the given XML</returns>
    /// <exception cref="System.ArgumentNullException">Thrown if node is null</exception>
    /// <exception cref="System.ArgumentException">Thrown if the node is not the correct type</exception>
    /// <exception cref="EDXLSharp.ValidationException">Thrown if the object fails to validate</exception>
    public static LocationExternalPolygon Parse(XmlNode node)
    {
      LocationExternalPolygon lep = new LocationExternalPolygon();
      lep.ReadXML(node);
      return lep;
    }
  }
}